Yup I've tried them. They're not with the money. I've used them on 2 different scoots and there was no improvement. The first one I bought hoping for an improvement and there was nothing. The second time I bought one for my CV80 because my stock coil broke. It worked fine, but no better than stock.

If a higher powered ignition coil really was able to squeeze more power (and thus efficiency) out of the same air/fuel mix then all manufacturers would put them in stock.